duffpkg

I am absolutely not in the UK. I am in the southwest.

It is in a utility room with some normal fire resistant features, walls are block and the electric inverters are mounted to cement board. The batteries cells themselves are in the steel cased battery boxes which help to limit potential fire risk. Very importantly these are lithium iron phosphate NOT lithium ion. There is still some fire risk with lifepo3 batteries but it is completely different than the thermal runaway possible with lithium iron.

Absolutely. Clouds also have a profound effect on solar output, I think much more than people realize. I am not english but my understanding is that london has a lot of clouds.

That is a much more complex topic driven by the regulations where you live. Where my house is, there is more or less no regulation and you can do as you please. In a purely technical sense there is not a lot of knowhow beyond basic electrical understanding, to setup these systems. Physically speaking these 280ah or larger battery setups are VERY heavy, hundreds of pounds per unit.

This area has few days over 100 but does see relatively cool nights. It is an ideal area for this. I would say from southernmost california to southernmost texas, this basic setup is pretty workable and that includes something around 50 million americans. Regulator hurdles in some places make it impossible though. Costs are going to scale up mostly in line with the heating/cooling requirements and cloudiness of your area.

My panels are ground mounted and pointed in the ideal direction. I think this contributes to their efficiency because the ground helps cool them during the hottest periods but it is a tricky thing to nail down. On a previous home I had roof mounted panels and they seemed to perform much worse, difficult to identify the exact reason though.

My battery is 3 separate "48v" x 280ah units in parallel. There is no grid so I am not sure what you mean by coupled. The batteries output DC to inverters which output AC. It is several years old at this point, probably the better value is in "48v" x 320ah setups now. The breakers/busbars, etc are setup for max discharge of 200A but in practice I have never gotten anywhere near that.

People seem to get really mad and accusatory over these sorts of things which is why I hate posting brands and such. The information changes very frequently as to what the "best" offer is. The diysolarforum is a very good resource to find the latest information.

In it's location the solar is very effective, the 4kw is the actual generation rather than a label rating. 100% full sun, no shade, no clouds. The array typically generates over 20kw per day. The house is pretty efficient and the weather is very nice both summer and winter. This is not an area with a harsh winter or summer.

Shade and clouds of any kind, even very minor, have a HUGE effect on the production of a solar array.

If I had to recommend in all in one kit, this september 2025, I would recommend an EG4 kit from Santan Solar. At brief glance they appear to be a stronger value and is from a company with a pretty strong customer service record. This is not sponsored in anyway.

I did not name specifics because things are constantly changing in this market and these threads tend to live for years. Stock and prices are constantly changing but RUiXU, EG4 and EcoWorthy are widely available brands with UL listed options. Will Prowse's website has a page dedicated to code compliant batteries and there are several long lists and excel sheets on the diysolarforum.

In that part of southwest there are only a handful of cloudy days per year and at a relatively low latitude.

It would be multiple batteries totaling that. Stock and prices are constantly changing but RUiXU, EG4 and EcoWorthy are widely available brands with UL listed options. Will Prowse's website has a page dedicated to code compliant batteries and there are several long lists and excel sheets on the diysolarforum.

I have a home in the southwest that is offgrid and runs entirely off solar. It has a 43kwh battery that covers 100% of it's needs including AC. It has a 4kw solar array.

The batteries shipped to your home inclusive of all taxes and fees, UL listed, are only $5,400 today from a variety of reputable suppliers.

This is obviously different than urban london but I wanted to point out just how economical this is for huge swaths of the country and how absolutely absurd some of the pricing I see on things like tesla powerwall are.

Note: There are a lot of components to an installed battery system that effect pricing such as racking, wires, busbars, breakers, etc, etc. I am referring only to the enclosed battery units with BMS.

This is a sketchy article about a study which is not even named because it has not yet been presented. It will be presented in the next week. I would take this entire thing with a grain of salt.